β-Cell Dysfunction in Adolescents and Adults with Newly Diagnosed Type 2 Diabetes Mellitus

ObjectiveTo compare β-cell function in adolescents and adults with newly diagnosed type 2 diabetes (T2DM).Study designThirty-nine adolescents with T2DM, 38 age- and weight-matched control subjects, and 19 adults with T2DM were studied. The adolescent subjects with diabetes were divided on the basis of whether they needed insulin to control their initial hyperglycemia. The primary outcome variable was the disposition index, computed from the acute insulin response to glucose corrected for insulin sensitivity (1/Homeostatic model assessment of insulin resistance).ResultsThe disposition index was significantly reduced in all 3 diabetic groups (control n = 3360, adolescents with T2DM without insulin n = 630, adolescents with T2DM with insulin n = 120, adults with T2DM n = 200; P < .001), and the adolescents with more severe hyperglycemia at diagnosis had lower disposition index than those with a more modest presentation (P < .05).ConclusionAt the time of diagnosis, adolescents with T2DM have significant β-cell dysfunction, comparable with adults newly diagnosed with T2DM. Thus, severe β-cell impairment can develop within the first two decades of life and is likely to play a central role in the pathogenesis of T2DM in adolescents.